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From bronchial mucins of cystic fibrosis patients with blood group 0, the carbohydrate chains were released in the form of oligosaccharide-alditols by alkaline borohydride treatment. Application of high-performance liquid chromatography directly on the pool of neutral oligosaccharides afforded 23 fractions. Twenty oligosaccharide structures were characterized by employing 500-MHz 'H-NMR spectroscopy in conjunction with sugar analysis. Thirteen among these had been revealed before to occur in human bronchial mucins [Van Halbeek, H., Dorland, L., Vliegenthart, J. F. G., Hull, W. E., Lamblin, G., Lhermitte, M., Boersma, A., and Roussel, P. (1982) Eur. J . Biochem. 127, 7 -201, when paper-chromatographic fractionation of this pool of neutral oligosaccharides was employed. High-performance liquid chromatography enabled to obtain another seven pentasaccharide and hexasaccharide alditols ; the largest-size representatives are :Thereby, this approach afforded deeper insight into the structural heterogeneity displayed by the carbohydrate chains of bronchial mucins.The tracheobronchial secretion is an important component of the mucociliary system which protects the airway mucosa by removing the dust particles that are inhaled. It contains highly viscous, mucous glycoproteins (so-called mucins) the carbohydrate moiety of which determines, to a large extent, the characteristic rheological properties of the respiratory mucus necessary for the efficiency of the system. Under pathological conditions characterized by bronchial hypersecretion like, for example, cystic fibrosis, the functioning of the mucociliary system is disturbed, leading to bronchial obstruction which may induce infection of the airways and increase the gravity of the disease.In order to determine whether these phenomena are due to an alteration of the structure of the bronchial mucins, we decided to investigate the carbohydrate structure of bronchial mucous glycoproteins obtainable from patients suffering fromAbbreviutions. Fuc, L-fucose; Gal. D-galactose; GlcNAc, Nacetyl-D-glucosamine ; GalNAc, N-acetyl-o-galactosamine ; GalNAc-01, N-acetyl-D-galactosaminitol ; hplc, high-performance liquid chromatography; NMR, nuclear magnetic resonance. cystic fibrosis. In a previous study [I], the isolation and characterization of 14 neutral oligosaccharides from this source was described. The applied isolation procedure comprised anion-exchange chromatography of the pool of neutral oligosaccharides, followed by preparative paper chromatography of the various fractions. Since this procedure consumed rather large amounts of time and material [l], it was decided to try an alternative approach, namely, purification of the oligosaccharides by direct high-performance liquid chromatography (hplc) of the neutral pool.Here, we describe the separation by hplc of at least 20 oligosaccharide fractions from cystic-fibrosis mucins. For characterization of the structures of the constituting oligosaccharides, 500-MHz 'H-NMR spectroscopy was applied in conjunction with carbohydrate anal...

Human blood‐group A active glycoproteins from ovarian‐cyst fluid were subjected to Smith degradation and subsequent β‐elimination. The resulting oligosaccharide‐alditols represent the core and backbone domains of the O‐linked carbohydrate chains. Nine of these, ranging in size from disaccharides to hexasaccharides, were investigated by 1H‐NMR spectroscopy. Their primary structures could be adequately characterized. In particular, the core types, i.e. the substitution patterns of N‐acetylgalactosaminitol (GalNAc‐ol) as well as the types of backbone, i.e. the linkage types of alternating Gal‐GlcNAc sequences, were unambiguously identified. The core type GlcNAcβ(1–3)GalNAc‐ol is described for the first time as occurring in ovarian‐cyst glycoprotein.

Human gamma-interferon (IFN-gamma) was prepared biotechnologically using Chinese hamster ovary cells. These cells were shown to be able to produce glycosylated IFN-gamma. Sugar analysis revealed the presence of Man, Gal, GlcNAc, NeuAc and Fuc residues in a molar ratio of 3.8:2.0:3.5:0.6:0.4 suggesting the occurrence of N-glycosidically linked N-acetyllactosamine type of carbohydrate chains. For structure determination of these chains, the glycoprotein was subjected to the hydrazinolysis procedure, yielding oligosaccharide-alditols. The latter compounds were analysed by 500-MHz 1H-NMR spectroscopy. The carbohydrate material was found to consist of biantennary structures, exhibiting microheterogeneity as to the terminal sialic acids and the core Fuc residue: (Formula: see text). As similar carbohydrates are present on several human secreted proteins, this glycosyl group is not expected to be immunogenic in man. It remains to be established to what extent the carbohydrate chains of this biotechnologically produced IFN-gamma are identical to those of naturally occurring human IFN-gamma.